The demand for mobile data and voice communication continues to evidence significant growth. Examples for mobile communication systems include cellular-based wireless communication networks. Such networks include various network nodes. The network nodes may include base stations which respectively provide coverage for a radio cell.
A user equipment of a mobile communication network may be a Proximity Service (ProSe) enabled device. Several ProSe enabled user equipments which are located in proximity to each other are operative to perform device-to-device (D2D) communication. D2D communication allows user equipments of a mobile communication network to directly communicate with each other when the user equipments are located in proximity to each other. D2D communication has a wide variety of applications, including public safety and other use cases. Emergency calls are one example for public safety use cases of D2D communication. Direct data or voice communication between user equipments is another example for use cases of D2D communication. For illustration, ProSe enabled user equipments located in proximity to each other may engage in data or voice communication.
Determining a relative position of a user equipment and at least one further user equipment may be required or beneficial in a wide range of application scenarios. For illustration, relative position information may be required for network control purposes, for estimating data rates or power consumption in D2D communication, for identifying suitable candidate user equipments which can engage in D2D communication, or other purposes.
Various techniques are available for establishing a position of a user equipment relative to a base station, e.g. relative to an evolved NodeB (eNB). Examples for such techniques include multilateration-based techniques such as OTDOA (“Observed Time Difference Of Arrival”).
Such techniques may not always be appropriate for determining relative positions of a user equipment and at least one further user equipment. For illustration, signaling overhead or power consumption may become large.